H20 Pump

[tee-boy]

What's this I hear about overheating an o/b and the plastic pump impeller burning up? Is it that the impeller melts or is it a bearing that fails/seizes? What's going on with that?

 

[Paul Moir]

Re: H20 Pump

If you operate an outboard without water, it's impeller burns up, and then the engine overheats. It's the rubber impeller itself that burns. New, one looks like this:<br />

<br /><br />And fit into a pump housing in which it turns like this:<br />

<br /> <br />Without lubricating the vanes with water, it's pretty easy to see how they burn up quick.

 

[quantumleap]

Re: H20 Pump

The overheating can occur two ways: The first is the vanes get ruined and don't move water efficently enough to cool the powerhead. The second is once the rubber starts to melt and break-up, fragments can lodge in the the cooling passages of the powerhead and cause it to overheat. Both are caused by running the motor out of water or with the intake ports blocked by weeds, mud etc. Always check the tell tale for constant flow.(If your motor has one.) BTW, nice pics Paul!

 

[tee-boy]

Re: H20 Pump

great help! thanks.